The present invention is an improvement on the test tube racks provided in the prior art, as exemplified by the systems disclosed in U.S. Pat. Nos. 3,379,315 (Broadwin), 3,233,804 (Dahm), 3,778,232 (McMorrow, Jr.), 2,189,989 (Lichtman), 3,674,198 (Eberle) and 4,068,798 (Rohde).
In particular, there are test tube racks available for all of the different sizes of manufactured test tubes. However, in order to meet the needs for any one experiment, perhaps as many as four different types of test tube racks must be easily within reach to store different sizes of test tubes containing various chemical solutions. This is an inefficient use of laboratory benchtop space characteristic of the prior art.
Another shortcoming of the currently available test tube racks concerns the requirement for long-term storage of multiple types and sizes of support racks. The different racks generally cannot be stacked together, and hence do not make efficient use of storage space.